First making an appearance late last week, the marine algal bloom commonly known as “red tide” has made its way back to the Shenzhen bay causing serious pollution as well killing off many marine plants.

The public have been issued warnings ‘strongly urging’ them to stay away from the polluted sea or eat seafood products from the area. These reports follow a series of warnings in other cities across China over the last couple of weeks, suffering from blue-green foul-smelling algae in their water.

“This is the biggest red tide that has ever appeared off the city’s coast,” said Zhou Kai, a marine expert with Shenzhen’s municipal sea fishery environment monitoring station.

Zhou Kai said this marked the third time this year a red tide had appeared off Shenzhen. The first appeared near Shenzhen bay in January and another appeared near Dameisha last month.

Based on the monitoring station’s observations, the most recent red tide is mainly west of Shenzhen infecting an area thought to be about 50 square kilometers.

A red tide has also been spotted near neighboring Hong Kong in the past few days, with as many as six beaches in Tunmen and Qingshan Bay being affected where local government has reminded people not to swim in polluted areas.

The red tide is said to be caused by a buildup of marine plankton that consume oxygen while releasing toxic substances into the water, killing off fish and plant life.

Zhou said the red tide would recede if it rained. “But the weather remains sunny and hot, which means the red tide is here to stay for now,” he added. He said the recent rain and hot weather conditions were favorable to the plankton who feed off the nutrients.

According to Zhou, few people would be affected economically as breeding sea fish is not vast in the area.

“But the foul smell of the dying algae will be unpleasant for the people living in the affected areas, and the tide’s annoying red color will also mar the pleasant view,” he said.

Dana Gornitzki

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